Upcoming in Rocheport, Mo.
Frog Calls and Look Alike Species: A Detective Story
Presentation by Carl Gerhardt, PhD, University of Missouri & NatureView Media

Photo of a gray treefrog (Hyla versicolor). Copyright by Carl Gerhardt.
Presentation by Carl Gerhardt, PhD, University of Missouri and NatureView Media
Tuesday, March 13, 2018
- 7 p.m. presentation (6 p.m. Social Hour)
- lower level of the Les Bourgeois Vineyards Bistro in Rocheport, MO
- Map and Directions
The Bistro Restaurant is now closed on Tuesday, but the bar will be open. You ARE welcome to come early, bring some food and gather with friends before the presentation. Speaker Series attendees are welcome after 5 p.m.
Missouri has an abundance of frogs that depend on pools and ponds in the floodplain of the Missouri and other rivers and streams.
Carl Gerhardt, a retired biologist with the University of Missouri-Columbia who has been studying frog vocal communication, will discuss the fascinating story of the common gray treefrog. It turns out that what we know as the common gray treefrog is at least two different species that can only be told apart by differences in the male call.
Carl discovered the properties of the call that are used by females to recognize males of their own species and to even distinguish among those males to select males that provide “good genes” to her offspring. He’ll share the story of his discovery as a detective story. The latest puzzle regards the evolutionary origins of one of the two species by a form of “instant” speciation – a doubling of the chromosome number.
Carl will play back and describe the calls of the two species: the eastern gray treefrog (Hyla versicolor), which is a tetraploid (4 sets of chromosomes) and the only species found in Boone County and Cope’s gray treefrog (Hyla chrysoscelis), which is a diploid like all other frog species in the USA and which occurs in the southern and northern parts of the state.
He will also describe his playback experiments to females. By using computer-generated calls, he identified the physical properties of the calls that females not only use to find a male of her species in places where both occur but also to find a male of her own species whose sperm will improve the viability and growth rate of her offspring. He will also describe the discovery of multiple origins of the eastern gray treefrog (yes, there are two, if not three origins) and the probable existence of different species of the Cope’s gray treefrog.
Directions
- 14020 W. Hwy BB, Rocheport, MO
- Take I-70 to the Rocheport, MO, exit (Exit #115). It’s the first exit east of the Missouri River.
- Head north toward Rocheport.
- After about a mile, turn left at the sign for Les Bourgeois Bistro. Follow the signs to the Bistro. You will probably need to park in the lot above the Bistro and walk the trail down.
- The presentations are held in upstairs in the restaurant. The restaurant is no longer open on Tuesdays but the bar is! You are welcome to bring your own food or snacks.
Resources and Links
Dig deeper into this topic
- Carl Gerhardt Lab site
- NatureView Media – Carl’s photography and film company
- ARTICLE – “Song of the Pond” by John Beahler, Illumination magazine
- ARTICLE – “Ask a Naturalist – Gray Treefrog or Cope’s Gray Treefrog”
- BOOK – “The Frogs and Toads of North America: A Comprehensive Guide to their Identification, Behavior and Calls” – By Lang Elliott, Carl Gerhardt and Carlos Davidson
- Carl’s videos on Vimeo
The Big Muddy Speaker Series in Rocheport
is hosted by these wonderful partners.
Click here for a list of upcoming presentations»
Special thanks to Les Bourgeois Vineyards for giving us the opportunity to use their beautiful space overlooking the Missouri River. All speakers are presenting for free! Thank you all for sharing your knowledge with us!
The Big Muddy Speaker Series also takes place monthly in Kansas City and St. Charles.
The Big Muddy Speaker Series is partially funded by the Mo. Dept. of Conservation.